Oxygen injection nozzle with externally projecting conduits



Ma h 4, 1969 w. v. BERRY 3,430,939

OXYGEN INJECTION NOZZLE WITH EXTERNALLY PROJECTING CONDUITS Filed April2, 1965 AT TORNE VS United States Patent 3,430,939 OXYGEN INJECTIONNOZZLE WITH EX- TERNALLY PROJECTING CONDUITS Walter V. Berry,Pittsburgh, Pa., assignor to Berry Metal Company, Harmony, Pa., acorporation of Nevada Filed Apr. 2, 1965, Ser. No. 445,100

US. Cl. 26634 18 Claims Int. Cl. C21c 5/46; B05b 15/00 ABSTRACT OF THEDISCLOSURE An oxygen injection nozzle head for forming a hightemperature furnace oxygen injection lance by jointure to a shank havingconcentric fluid-conducting channels therein, the nozzle head having asubstantially spherically curved oxygen-ejecting face with a pluralityof water cooled oxygen-emission passageways with wall portions thereofprojecting beyond the face surface and defining an intermediate spacetherebetween, said passageways opening as ports, at least a portion ofeach of said wall portions being of double-walled thickness to providean internal fluid-flow cavity therein and adjacent to each of saidpassageways.

This invention pertains generally to injection lances for use in hightemperature furnaces, and more particularly to an improved injectionlance nozzle that will deliver a sustained high quality performancewhile withstanding the rigorous environmental conditions common to alltypes of furnaces used in the basic metal industries.

In accordance with the prior art, of which I am aware, extensiveimprovement has been made in recent years in the process of steelmaking, and of particular importance has been the increase in productivecapacity of furnaces due to the introduction of oxygen directly onto themolten bath within the furnaces. Various types of injection lances havebeen developed to introduce the oxygen into the furnace, and theextensive benefits obtained through the use of injection lances hasfostered considerable experimentation to improve their operationaleffectiveness. The end of the lance, commonly referred to as the nozzle,has received considerable past attention. The short history of theinjection lance has been marked with much activity and many stages ofdevelopment in the construction of the nozzle in the interest ofimproving its function and extending its life.

My invention, Patent No. 3,043,577, is only one of many examples of thework that I have done in this area to improve the construction ofinjection lances. My work, like that of others in the art, has producedmany answers to the demand of the basic metal industries for increasedyield at less expense. However, in spite of the much improved lancesthat have been introduced into the art, I have concluded that furnaceoperators are nevertheless badily in need of an improved lance for theattainment of new thresholds of efficiency and economy. My most recentresearch and exhaustive experimentation has led to the invention of anovel compound nozzle for an injection lance, which because of theunique concepts embodied in its construction will provide furnaceoperators with a means to reach a new plateau in their quest for ahigher yield at lower cost. The development of the novel characteristicscontained in the construction of my present invention was originallysparked by my observation of certain shortcomings in nozzles of theprior art.

I had noticed that such nozzles suffered extreme deterioration due toparticles ejected from the bath. I had also observed that there is aneed for a method of con- 'ice trolling either the constant highvelocity direction of particles or its damaging effect to the exteriorsurface of the nozzle. I had further concluded that if possible suchcontrol must be achieved through radical changes in the construction ofthe nozzle itself. A further observation of mine concerned the effect ofthe extreme high temperature environment on the body of the nozzle.Softening of the base metal and subsequent distortion of the nozzle is aconstant problem.

The tendency for compound or multiorifice nozzles to cause, because oftheir design and construction, the creation of a vacuum core in thecentral region between the oxygen streams as they are emitted from thenozzle is another problem I have recognized. Natural forces cause atendency to fill the vacuum, and furnace gases with entrained particlestend to move through and between the emitting oxygen streams. The effectof the inrushing gases on the oxygen streams is to cause turbulence,distortion, diffusion and dilution. Accompanying variations of pressurein and around the streams caused by the central vacuum results inoscillation in speed and in direction of the streams. This directionaloscillation of the streams becomes an oscillation in effective force ofthe streams and is transmitted to the bath in the form of oscillatingpressures on the bath. The oscillating actions of the oxygen jetsthereby produce lance damage caused by slopping, sparking, and excessivesplashing and ejection of particles back toward the nozzle, as well asdamage to the walls of the vessel.

Generally, the major improvements that have been recognized as mostvitally needed, can be categorized to three major areas: (1) damage tothe nozzle from the molten bath, (2) poor heat removal per unit area ofnozzle surface, and (3) inefiicient use of the oxygen being injected.

It is accordingly an object of my invention to provide a nozzle head foran oxygen lance that, by means of the reduction of tap to tap time inthe operation of a reactor vessel. will greatly increase production.

It is another object of my invention to provide an oxygen injectionlance nozzle head that is of prolonged operating life in a hightemperature reactor vessel.

It is a further object of my invention to provide an improved lanceassembly for injecting oxygen into a furnace which obtains maximum useof the oxygen and a minimum waste.

It is an ancillary object to obtain a maximum supply of oxygen in thebath with a minimum of oxygen being carried off with waste gasesexhausting through the hood of the furnace.

It is also an object of my invention to provide a lance nozzle headhaving an increased internal cooling efiiciency so as to reducesoftening and distortion of the base material thereof.

An additional object of my invention is to provide a lance nozzle headwhich, through its unique exterior design, will substantially reducesurface deteioration.

It is a further object of my invention to provide a lance nozzle headincorporating into both its exterior surface configuration and itsinterior oxygen passages unique aerodynamic structural principles thatwill greatly improve the function of the lance and the overallefiiciency of the furnace operation.

It is an ancillary object of my invention to provide a novel and usefulprocess and apparatus for the improved refining of materials.

In accordance with my invention I provide a nozzle for an injectionlance assembly which contributes to the art by the unique solution ofthe problems previously outlined. First, the nozzle is only similar tothe prior art nozzles to the extent that it too is of a multiorificeconstruction. The outer configuration of my nozzle is radical- 1ychanged, leaving further resemblance between it and the nozzlespreceding it in the art, one strictly of function and purpose ratherthan appearance. Instead of the conventional arrangement of oxygen portsemitting from the smooth face of the nozzle, my invention introduces anozzle with its end surface divided into a plurality of faces, so thatthe oxygen ports no longer open from a common surface face. In thepreferred embodiment of my invention the face of the nozzle istrifurcated so that each of these three oxygen channels extends outwardbeyond the main body of the face of the nozzle and is housed in its ownseparate appendage. This departure from a conventional constructionresults in an ejection lance whose furthest end extensions appear toconsist of multinozzles, each housing its own oxygen channel having aseparate orifice therein. This multinozzle type of construction allowsfor a novel lance surface treatment that imparts numerous advantages.

The tendency of the downward rushing oxygen streams to create the vacuumin their midst can be beneficially compensated for so as to materiallyreduce the aforementioned adverse effects. The pathways for furnacegases moving in between each of the separate nozzles and its adjacentnozzle is sloped so as to be aerodynamically contoured inwardly and downtoward the direction of the molten bath so that all such pathways attheir points of origin are higher and substantially further from a baththan the oxygen emitting ports. These contoured pathways between theseparate nozzles slope inwardly and down to a common point coincidingwith the vertical axis of the lance. Furnace gases will no longer passthrough and between the oxygen streams as they are drawn into the vacuumcore, but are drawn in above the emerging oxygen streams and are feddown into the bath as a united stream that becomes coextensive with thecircumambient oxygen flow. The controlled motion of the flow of furnacegases across the face of the lance and down through the central coreassures minimal distortion and minimal fragmentational damage, thusincreasing the life expectancy of the lance. The controlled flow ofgases also serves to increase the efficiency of the operation, sincedilution, oscillation, and distortion of the oxygen streams areconsiderably reduced. In addition this provides a smooth and simpleprocess for oxidizing some of the carbon monoxide in the atmosphereabove the bath so as to produce cleaner waste.

In accordance with my invention I provide a novel system of watercooling so as to increase the lance life; improved external coating andconfiguration cooperating therewith for protecting the nozzle; and anovel configuration for the oxygen channels which prevents pumping bythe oxygen stream and cooperating with the exterior design of the lanceproduces a lance which substantially eliminates the problems of poundingor oscillation of the bath which is frequently caused by high velocityoxygen blowing.

The important features that I consider characteristic of my inventionare set forth in detail in the appended claims. However, theconstruction and function of the invention, together with additionalassociated objects and advantages will be best understood from thefollowing detailed description when read in connection with theaccompanying drawings in which:

FIGURE 1 is a side view of the lance head shown prior to its attachmentto the shank of the injection lance.

FIGURE 2 is a side view of the entire oxygen lance assembly, shown withits outer surface and interior channel walls partially cut away.

FIGURE 3 is an end view of the head or nozzle portion of the lance inaccordance with the preferred embodiment of my invention.

In accordance with my invention I provide a compound nozzle head for alance for the purpose of injecting fluid materials such as oxygen into asteel furnace in which the lance protrudes through the top of thefurnace and extends down into the interior thereof to a point preferablyabout six feet above the surface of the materials being treated therein.

Considered separately, the head of the lance as shown in FIGURE 1 hasthree annular shoulders 2, 6, and 12 located at higher horizontal levelsrespectively, with their relative diameters diminishing in the sameorder. The upper portion of the lance head beginning at the shoulder 2with the greatest diameter, which is on the lowest horizontal level, isin the form of a combination male and abutting insert to be fitted intoand against the female or receiving end of the lance shank to form afully assembled lance as shown in FIGURE 2. Each of the aforementionedshoulders 2, 6, and 12, at final assembly, is welded to a correspondingchannel wall 56, 58, and in the lance shank 54. The transverse weldsshown at 2, 6, and 12 in FIGURE 2, join the shoulders of the head to theannular walls of the shank 54, sealing and completing the formation ofthree vertical, coaxial channels 14, 30, and 32, in the final assembly.The three coaxial channels 14, 30, and 32 lead from the shank 54 andinto the head; and are the central oxygen tube 14, the incoming waterchannel 32 which is immediately circumjacent the central oxygen tube 14,and the outer coolant return channel 30 which is an annulus containedjust within the wall 56 of the final assembly shown by FIGURE 2.

1n the preferred embodiment of my invention the diameter of the centraloxygen tube 14 at the point 12 where it enters the nozzle head from theshank 54 is approximately equal to two-thirds of the total diameter ofthe lance shank 54. As this central oxygen tube 14 extends down into thehead, it separates into three tributarial tubes, one of which is shownby 18, FIGURE 2, which, in the embodiment shown, diverge from thevertical axis of the lance 54, each at an angle of approximately 10. Itshould be emphasized that other embodiments contemplated within thescope of this invention may have tributarial oxygen tubes such as 18branching from the central oxygen tube 14 wherein the angle of thebranch tubes in relation to the vertical axis of the lance 54 may fallanywhere within a range of 6 to 18.

Considering now the tributarial tube 18 revealed in the drawing inFIGURE 2, it will be seen that the internal configuration therein is aconverging-diverging nozzle. Each of the tributarial tubes is machinedto have an identical internal configuration as shown in this example 18.

Beginning at the point 34 where the annular wall of the tube 18 beginsto converge inwardly, and moving toward the exit port 62 of the tube tothe throat 20 where the convergence of the annular wall ends, thisportion of the nozzle can be described as an embodiment of the DeLavalnozzle, as first documented by the Swedish engineer, DeLaval. Thediverging motion of the nozzle from 20 to 26 in one embodiment of myinvention, is a curved wall formed by striking an are from a point or aplane through the axis of the oxygen conduit 18 so that said divergingportion on a line from 20 to 26 is conical, with its surface wallslightly curved between the points 20 and 26. From the point at 26 ofgreatest divergence, downward to the end of the nozzle at 62 is acylindrical portion 24 approximating in length the length of theconverging-diverging portion which is from 34 to 26.

In regard to the cylindrical extended portion of the nozzle, it shouldbe emphasized that it has a twofold purpose. M. S. Kisenko, in hisComparative Results of Tests of Several Different Types of Nozzles, NACATM, 1066, June 1944, concludes that a nozzle with a conical divergencewhich ends with a cylindrical portion gives a better velocitydistribution than a conventional DeLaval nozzle. His observation hasproved to be correct. However, the cylindrical portion shown at 24 is ofa longer length than is necessary to satisfy Kisenkos theory. Theimproved velocity distribution available by use of an additionalcylindrical portion is not directly dependent upon the length of thecylindrical portion. Additional length is provided herein in order toperform a second function. Experience has shown that the edge 22 aroundthe port 62 will, over a period of time, begin to oxidize due to thepresence of the oxygen flow in contact with the high temperature surfaceof the structure. This reaction on the edge of the port is anticipated,and a long length cylindrical bore preceding the port exit 62 isprovided so that material erosion due to the aforementioned reactionwill not interfere with the primary purpose of the cylindrical bore.Although use over a long period may result in the edge 22 of theemitting port 62 taking on the configuration of a shallow flare, therewill always remain a substantial portion of the cylindrical portion 24to continue the aforementioned effect, as described by Kisenko.

Referring now to the lance portion 54 of the assembly shown in FIGURE 2,completely surrounding the central oxygen tube 14 is an annulus that isa channel 32 for incoming liquid coolant. Coolant flowing down throughthis annular passage 32, at a point just below the Welded shoulder 12,is separated into three separate inwardly leading channels as shown at8, FIGURE 1. This separation is caused by the presence of the outerwalls as shown in FIGURE 1, numeral 36 of the tributarial oxygen tubes18. Thus the incoming annular flow is split into three streams, each ofwhich is guided by an apron 4, FIGURE 2, which is the continuation ofthe outer channel wall 58, so that the incoming water flow is directedto cascade down and around the outer wall 64 of the tributarial oxygentubes so as to completely fill and circulate about the furtherestextension of the water jackets 66 that surround the oxygen tubes. Havingcompletely circled and inundated the lower extension of the annularpassage 66 around each of the tributarial oxygen tubes 18, the Waterthen flows up the return channel 30 which in the assembled lance is anannulus whose outer wall coincides with the outer wall 56 of theassembled lance.

Considering now the exterior configuration of the face of the nozzlehead (FIGURES l and 3), the nozzle head is provided with a base portion40 that is a spherically shaped face and protruding therefrom in acloverleaf design is a plurality of facial extensions 46, 48, and 50,which are called conduits, having in the center of their respectivefaces the jet-emitting ports as at 62. It will be observed that betweeneach two protruding, thick walled conduits, as between 46 and 48, thereexists a portion 44 of the main spherical face 40 of the nozzle suchthat there are three sloping channels or pathways 44, each beginningnear the outer edge of the spherical face at 52 and sloping over thesurface 40 of the face to converge with the other two pathways at apoint 47 which is the center of the spherical face. Said conduits 46, 48and 50 are spaced apart a distance such that the open spaces or pathways44 exceed or equal the cross sectional area of each orifice 22.

Having generally pointed out the structural formation of the nozzlehead, an explanation with reference to the accompanying drawing, of itsoperational function Within a reactant vessel will more clearly depictthe salient novel characteristics of the invention.

First of all, the instant invention is technically superior toconventional nozzle heads in that it will virtually eliminate a majorproblem previously encountered when the emitting oxygen jets werediluted and oscillated by the waste gases of combustion. The purpose ofthe converging-diverging nozzle 18 previously described is to create ajet flow with a velocity in the range of Mach 1.5 or above which willemit from the oxygen port 62 and continue to the bath below as a laminarflow.

In prior nozzles the emitting oxygen jet has a core wherein the flow islaminar, with a surrounding turbulent boundary layer. Following now thedownward motion of the jet in that type of nozzle, the boundary layerincreases in thickness and the core diameter decreases until itdisappears. At the point of disappearance the flo'w is then fullyturbulent. The improved construction of the instant invention,particularly the internal nozzle 18 construction, effectively delivers ajet flow the diameter of which is comparable in flow characteristics tothe core region in the flow emitting from conventional nozzles. It is myconception that two cooperating principles embodied in thecompound-nozzle head make possible the sustained laminar flow along theentire length of the jet from the nozzle head to the bath.

If two or more jets are at close distance each jet is partly shieldingthe others from the inflow of carbon monoxide; this inflow becomesasymmetric with respect to the centerline of each jet and the pressuredistribution on the jet boundary is also asymmetric. By Coanda effectthe jets tend to bunch together and to stay locked in this position atsome distance below the nozzle exit.

The environmental conditions in a basic oxygen furnace can be simplydescribed as a cold stream of oxygen jetting downward into a largevessel through an area filled with high temperature waste gases flowingin an upward direction. So, having established a superior method ofdelivering the oxygen streams toward the bath in a supersonic, laminarflow, subsequent control of the physical interaction of the waste gaseswith the oxygen streams through which the gases must penetrate willfurther enhance the efiiciency of the compound-nozzle head. In anymultiorifice nozzle there exists a vacuum, or low pressure regionbetween the onrushing streams of oxygen. Waste gases, including carbonmonoxide, rush through and between the oxygen streams to relieve the lowpressure condition therein and has the adverse effects of distorting theoxygens streams, intermixing and pulling them together with a resultingturbulence, then creating oscillation in the streams which istransmitted then to the bath. These effects heavily contribute torefractory and lance damage caused by resultant sparking and slopping.In the compound-nozzle head the carbon monoxide is directionallycontrolled to dissipate the aforementioned adverse effects. By extendingeach nozzle 18 in its own separate housing (such as 45), entrances areprovided between each of the two protruding conduits, as at 44. Thecarbon monoxide rushes to relieve the vacuum between the down rushingstreams along the contoured pathways 44 over the face of the baseportion 40 of the compound-nozzle head. The gases of combustion willenter and combine as a centrally flowing core in an area above andbehind the emitting oxygen jets 62. The pathways 44 converging acrossthe face of the base portion 40 of the compoundnozzle head presentsloping surfaces profiled to feed the inrushing gases so that the threeseparated flows of inrushing gases unite as a solid stream at 47. Theinwardly sloping pathways 44 also provide a means of reducing theadverse effect which is familiar in the prior art, when molten particlesor slag ejected from the bath strike the lance face. With thecompound-nozzle head, particles that may reach the vicinity of pathways44 will impact at an oblique angle to the surface. Thus, the contouredsurface will encourage the particles to richocet rather than entrainthereon.

Inasmuch as care has been taken to profile the facial surface of theentire compound-nozzle head for the functional purposes previouslydescribed, attention is directed to the possibility of coating orinlaying selected portions of the facial surface (FIGURE 3) whichincludes the base portion 40 with the projecting condits 46, 48, and 50.The careful blending of all surfaces where they adjoin, by a gradualsloping, would be conducive to adherence of a case material applied by acoating process. It may be found practical to undercut portions of thefacial surfa ce, and affix refractory materials or a selected alloythereto. The presence of the secondary layer of material afiixed to thefacial surface of the compound-nozzle head would be to protect the headitself by encouraging the flow of gases in the direction of the contours44, or by changing the rate of heat transference to the nozzle head, orby inhibiting the erosion of the facial surface due to particle impact.It is expressly stipulated that the application of a secondary layer ofa coating material as previously described may be found desirable. Thefuture application of such material is herein expressly anticipated andincluded within the scope of the invention.

An optional feature available in the instant invention has to do withthe possibility of using the lance assembly as herein described withcoolant flow flowing in a reverse direction; that is, having theincoming coolant flowing through what is now the exit channel 30 andusing the coolant channel 32 nearest the central oxygen tube 14 as theexit channel. A reversed coolant flow direction may be found desirablein actual use or in future experimentation, depending perhaps upon thenature of the site of operation, the desired distance of the lance endabove the bath, etc. However, referring now only to the direction of theflow established by the arrows in the drawing, it will be seen that theincoming water flow through the channel 32 in the lance shank 54 isdirected in a straight, downward flow which completely surrounds thecentral oxygen tube 14. The low temperature within the oxygen tube 14will have the incidental effect of cooling the wall 60 of the tube 14and thus will conduct heat away from the liquid within the channel 32.In this manner the liquid coolant along the entire length of the shank54 as it moves down the channel 32 is cooled sufficiently to offset anyheat transference from the outer wall 58 of the channel 32, said outerwall 58 being shared with the exit channel 30. For this reason the abovedescribed direction of coolant flow is considered the more desirable.

However, it is understood that in accordance with other embodiments ofmy invention the flow of coolant may be reversed and produce better flowcharacteristics in the nozzle although at the expense of employing awarmer coolant at the nozzle.

It should be emphasized that coolant flow is maintained. both incomingand outgoing, at a rapid vertical streamline flow within the lance shank54. At the point (as at 38) within the compound-nozzle head where theincoming flow is split into three separate streams, the structural wallis inwardly contoured to continue an unobstructed flow. Turbulence inthe coolant flow to assure a scrubbing action to remove steam bubbles orair pockets on the surfaces of the coolant passage 66 is introduced whenthe incoming coolant, after having been directed .down and around theouter walls of the oxygen tubes, smashes into the ridge-like separationsat 68, which are the inside surfaces of the outer contoured passageways44 previously described. These ridges 68 formed on the inside surface ofthe base portion 40 act as deflectors to split the merging coolant flowand guide the coolant to the extreme ends of the jacket passages 66.

It will be noted from the drawing and the foregoing description that theprojecting conduits which are them-- selves water cooled, tend toprotect the region therebetween from excessive radiation. For example,the bottom portion of the groove between adjacent projecting conduitscan only receive radiation coming from a region of the bath through anangle of about 10 or Radiation from other sections of the bath cannotreach the bottom of this groove or canyon because the bottom portion isshielded by the adjacent protruding conduits. Thus, by the configurationwhich I employ radiation damage in the :egion near the center of thelance is effectively eliminated.

Other embodiments within the scope of this invention are contemplated.One example would be the inclusion in the assembly as here described ofa vertical, axial pipe which would have one end beginning in the centerat 47 of the base portion of the compound-nozzle head. The opening ofthe pipe would be of a small enough diameter not to interfere with thepurpose of the contoured pathways 44 across the face of the base portion40 of the head. This pipe would extend in such a manner that its axiswould coincide with the axis of the lance shank 54. Such a pipe, ifincluded in the structure, might lend itself to a variety of uses: itmight be employed as a means of viewing the bath directly from above; itmight be used as a central passage through which to obtain gas samples;or it might be employed as a passage through which to extend athermocouple to gauge the temperature of the bath, or to injectadditional ingredients into the furnace.

There is an upper limit to the relative particle velocity which anymaterial can sustain upon impact. When this limiting value is exceededthe material parts in a brittle manner. This limiting value is calledthe critical relative particle velocity of the material and is relatedto a critical dynamic fraction strength. The limiting velocity isnormally taken to be the same as the experimentally determined criticalimpact velocity of the material. For copper the theoretical criticalvelocity is 260 feet per second and the experimental critical velocityis 200 feet per second. Thus in accordance with one embodiment of myinvention the size of the region between projecting conduits may bedefined as that size aperture through which an adequate supply of gasmay pass to fill the vacuum created by the oxygen jets without causingthat gas to exceed a velocity of 200 feet per second as it approachesthe axis of the lance. This definition is, of course, based on theassumption that the particles are eflectively entrained by the gas andtherefore the velocity of the particles will be substantially equal tothe velocity of the gas. This conception may better be understood bythose unfamiliar with the terminology involved by reference to thepublication The High Velocity Forming of Metals, published by the ASTMDwith particular reference to the discussions around page 27.

While I have emphasized herein a compound nozzle having three nozzles,nevertheless, it is understood that four or more nozzles might beemployed in forming a compound-nozzle head. It is also understood thatwhile I have shown the throat to comprise a single annular line,nevertheless, in accordance with other embodiments of my invention, thethroat may be of finite width, e.g., the throat of each nozzle maycomprise a short section of cylindrical shape.

Although I have shown and described specific embodiments of myinvention, I am fully aware that other modifications thereof arepossible and may eventually be desirable. The invention therefore is notto be restricted except insofar as is necessitated by the prior art.

I claim as my invention:

1. A compound nozzle head for forming an oxygen injection lance by itsjointure to a shank having concentric fluid-conducting channels therein,said nozzle head comprising a substantially spherically curved facehaving a plurality of material ejection conduits protruding therefrom,the ends of said conduits opening as ports having respectivelytherearound wall portions projecting beyond said face and definingtherebetween an intermediate space, each of said Wall portions of saidconduits having passageways for water cooling and protruding a distanceapproximately equal to the diameter of each of the ports of saidejection conduits as measured along their sides nearest the axis of saidnozzle.

2. An oxygen lance compound nozzle head to be aflixed to a shank to forman oxygen lance made to project down into a furnace, said nozzle headbeing cored to receive a fluid coolant flow from said shank, saidnozzles head having internal passageways to accommodate said coolantflow from said shank, through said nozzle head and back through saidshank, said nozzle having a central internal oxygen conduit to conduct adownward oxygen flow from an interconnecting conduit in said shank, saidnozzle head having an outer geometrically solid spherical configurationforming a base portion having extended therefrom a plurality ofidentically shaped water cooled nodular heads, said heads housing theexit ports for said downward oxygen flow.

3. An oxygen lance compound nozzle for injecting combustion materialsinto a high temperature furnace comprising a geometrically solidspherically curved face having protruding therefrom a plurality ofmaterial ejection conduits, said conduits being water cooled andprotruding a distance approximately equal to the diameter of the exitopenings of the ejection conduits, as measured along the sides of theconduits nearest the axis of said nozzle.

4. A compound nozzle head for injecting oxygen into a steel furnacecomprising a substantially spherically curved face having protrudingtherefrom a plurality of material ejection conduits, said conduitshaving passageways for water cooling and being spaced apart .a distancesuch that the open space defined by the face of the nozzle, adjacentconduits, and a line between their exit openings exceeds the crosssectional area of each of the orifices.

5. A compound nozzle head for injecting oxygen into a steel furnacecomprising a substantially spherically curved face having protrudingtherefrom a plurality of material ejection conduits, said conduitshaving passageways for water cooling and being spaced apart a distancesuch that the open space defined by the face of the nozzle, adjacentconduits, and a line between their exit openings is substantially equalto the cross sectional area of each of the orifices.

6. A compound nozzle head for an oxygen lance comprising ageometrically-solid configuration in the form of a base portion with aplurality of nodular heads housing oxygen passages the rethrough leadingto respective oxygen exit ports, and a coolant flow region around theoxygen passages, said heads protruding from said base portion.

7. A compound nozzle head for injecting oxygen into a steel furnacecomprising a substantially spherically curved face having protrudingtherefrom a plurality of material ejection conduits, said conduitshaving passageways for water cooling and being spaced apart a distancesuch that the open space defined by the outer walls of adjacentconduits, the face of the nozzle and a line between their exit orificesexceeds the cross sectional area of the orifices, and said conduitscomprising double walls spaced apart for circulation of coolanttherethrough.

8. An oxygen lance compound nozzle to be affixed to a shank to form anoxygen lance made to project down into a furnace, said nozzle havinginternal passageways to accommodate coolant flow from said shank,through said nozzle, and back to said shank, said nozzle having acentral internal oxygen conduit to conduct a downward oxygen fiow froman interconnecting conduit in said shank, said nozzle having .ageometrically solid substantially spherically shaped face with aplurality of identically shaped water cooled nodular heads extendingtherefrom, said heads housing the exit ports for said downward oxygenflow.

9. An oxygen lance nozzle as described in claim 2 having an ancillaryopen end axial passage extending from the midpoint of said sphericalbase portion vertically along the axis of said nozzle to aninterconnecting passage provided in said shank, said axial passagecontained for its full length by a cylindrical wall, said passageextending from said spherical base portion and up through andcoextensive to said central oxygen conduit.

10. In an oxygen lance for feeding oxygen into a reactor vessel, anoxygen lance compound geometrically solid spherically shaped nozzle headhaving an emitting end portion comprising a base portion with aplurality of protruding water cooled conduits, each of said conduitshaving a central coextensive oxygen emitting tube, said tube including aportion having an internal configuration of a converging-diverging jetnozzle.

11. Apparatus as described in claim 10 in which said tube extends beyondsaid converging-diverging nozzle as a cylindrical bore ending as a jetemission port on the face of said conduit.

12. Apparatus as described in claim 11, characterized by saidcylindrical bore and said conduit through which said bore extends beingprojected to a length wherein the length of said cylindrical bore isgreater than the length of said converging-diverging nozzle.

13. An oxygen lance nozzle for injecting oxygen into a steel furnacecomprising a geometrically solid spherically curved face havingprotruding therefrom a plurality of material injection conduits, saidconduits being spaced apart a distance such that the open space definedby the face of the nozzle, adjacent conduits, and a line between theirexit openings exceeds the area of each of the orifices of said conduits,said spherically curved face having its surface regions joined bycontoured surface portions so that none of the regions of the surfacethereon are sharply delineated, said spherically curved face havingportions thereof with a thin heat resistant layer.

14. An oxygen lance nozzle for injecting oxygen into a steel furnacecomprising a geometrically solid spherically curved face havingprotruding therefrom a plurality of material injection conduits, saidconduits being spaced apart a distance such that the open space definedby the face of the nozzle, adjacent conduits, and a line between theirexit openings is substantially equal to the area of each of the orificesof said conduits, said spherically curved face having its surfaceregions joined by contoured surface portions so that none of the regionsof the surface thereon are sharply delineated, said spherically curvedface having portions thereof with a thin layer of reflective,abrasion-resistant material.

15. The oxygen lance compound nozzle recited in claim 2, furthercomprising a plurality of external contoured pathways for inducing theformation of a central vacuum core in a space centrally defined by saidplurality of nodular heads, each of said pathways defined by the surfaceof said base portion and wall portions of adjacent nodular heads.

16. An oxygen lance compound nozzle head joined to a shank to form anoxygen injection lance with said head extended toward a molten bathwithin a furnace, said head cored to receive a fluid coolant flow fromsaid shank, a plurality of internal passageways within said head toaccommodate said coolant flow from said shank through said nozzle headand back to said shank, said head having a central internal oxygendistribution conduit for conducting a downward oxygen fiow from aninternal interconnecting conduit within said shank, said head having abase portion with a substantially geometrically solid spherically curvedface, a plurality of identically shaped water cooled nodular projectionson said face, each of said projections having an axial passagewayopening as an oxygen port centrally on the outer end thereof, the axisof each said projections diverging at an angular relationship to theaxis of said shank, each two adjacent projections having therebetween acontoured pathway formed by the face of said base portion and surfaceportions of said projections for conducting circumambient gases risingfrom said molten bath in a direction toward an extension of thelongitudinal axis of said lance.

17. A compound nozzle head for forming an oxygen injection lance by itsjointure to a shank having concentric fluid-conducting channels therein,said nozzle head com prising an oxygen-ejecting face that issubstantially spherically curved, with said face having a plurality ofoxygen-emission passageways provided therein, the ends of saidpassageways, opening as ports having respectively the rearound wallportions projecting beyond the level of said face and definingtherebetween an intermediate space, each of said wall portions having atleast a portion thereof of double-walled thickness to provide aninternal fluidflow cavity therein and adjacent to each of said passgeways.

18. An oxygen injection nozzle head for forming a high temperaturefurnace oxygen injection lance by jointure to a shank having concentricfluid-conducting channels therein, said nozzle head having asubstantially spherically curved face with a plurality of water-cooledoxygen-emission passageways opening as ports, wall portions about saidpassageways and said ports, said wall portions projecting beyond saidnozzle head face and defining an intermediate space therebetween, atleast a portion of each of said wall portions being of double-walledthickness, whereby there is provided an internal fluid-flow cavity in atleast a portion of each of said wall portions adjacent to each of saidpassageways.

References Cited UNITED STATES PATENTS 3,322,348 5/1967 Vonnemann266-34X 3,065,916 11/1962 Kurzinski 26634.1X

J. SPENCER OVERHOLSER, Primary Examiner.

E. MAR, Assistant Examiner.

US. Cl. X.R.

